Lijekovima uzrokovana imuna trombocitopenija – prikaz bolesnice

Abstract

Thrombocytopenia is defined as a reduced platelet count. Drug-induced immune thrombocytopenia (DITP) is a condition mediated by antibodies developed following the ingestion of a certain medication. A sudden drop in platelet count accompanied by ecchymosis, petechiae, and mucosal bleeding following the introduction of a new medication should raise suspicion for DITP. This case report describes the case of a 76-year-old female patient who first appeared at the Emergency Department (ED) with symptoms related to heart failure and atrial fibrillation. The patient was taking warfarin as an anticoagulant therapy when she presented herself to the ED. Following a short hospitalization at the Cardiology Department, the patient was discharged home with dabigatran instead of warfarin as the anticoagulant therapy. After several days of taking dabigatran, the patient came to the ED with a chief complaint of dark-colored urine. Her platelet count (measured using a machine and manually counted) was 13×109/L, and the urinalysis was positive for microhematuria. Dabigatran was excluded from the patient’s medication list. At a later date, following the patient’s request, she started with rivaroxaban prescribed by her general practitioner. The test for anti-platelet IgG antibodies (performed while the patient was taking dabigatran and later rivaroxaban) was positive. Therefore, rivaroxaban was also excluded from the patient’s medication list. After the platelet count normalized, warfarin was reinstituted into the patient's therapy. Due to the diagnosis of DITP being most often empirical, clinicians should suspect DITP if there is a sudden drop in the platelet count accompanied by signs of bleeding following the introduction of a new medication in the patient’s therapy. Additional laboratory workup for transfusion reactions should be conducted, while the culprit medication should be excluded from the patient’s medication list without delay.